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The present investigation was carried out to study the effect of seed treatments of lupine plants (cv.Giza 2) with chemical inducers Bion (5mM), salicylic acid (5mM) and saccharin (3mM) as well as Paenibacillus polymyxa and Trichoderma harzianum as biotic inducers on the infection with Rhizoctonia solani and Fusarium oxysporum f. sp. lupini under greenhouse and field conditions. Under greenhouse condition (Agricultural Research Centre, Giza) all treatments significantly reduced the percentages of pre-and postemergence damping-off compared with the untreated control, the highest percentage of survived plants was achieved 92% by Bion and T. harzianum as well as fungicide Rizolex-T followed by salicylic acid and P. polymyxa as 88%. On the other hand, all treatments decrease significantly the incidence and severity of wilt, also increased the percentage of survived plants compared with untreated control. Under field conditions at Giza and Ismailia Agricultural Research Stations (Giza and Ismailia governorates) during winter season 2016-2017, all the treatments decreased the percentage of preand post-emergence damping-off as well as the percentage of wilted plants and increased the percentage of survived plants compared with untreated control in two locations. At Giza research station, the highest percentages of survived plants were recorded with Rizolex-T followed by Bion, P. polymyxa, and salicylic acid. While at Ismailia, the highest percentage of survived plants were recorded with Rizolex-T followed by Bion, P. polymyxa, T. harzianum, and salicylic acid. Meantime, these treatments improved growth parameters i.e. plant height, number of pods/plant, the weight of seeds /plant and the weight of one hundred seed. The higher increase in seed yield (ton /feddan) was obtained with Rizolex-T and Bion treatments followed by Salicylic acid, P. polymyxa, and T. harzianum at two locations. Activities of peroxidase (PO), polyphenol oxidase (PPO) enzymes and phenol content were determined. Bion treatment showed the highest increase in PO and PPO activity, and total phenols followed by salicylic acid and P. polymyxa treatments in the presence of R. solani or F. oxysporum. f. sp. lupini.

Plant Growth Promoting Rhizobacteria (PGPR) were evaluated individually or in combination and compared to the fungicide Topsin M-70 ® for their antagonistic activities and suppressive actions against Fusarium oxysporum and Rhizoctonia solani severally, which were deemed the causal agents of root rot and wilt diseases of faba bean plants. In vitro, most of the examined strains showed eminent abilities to inhibit mycelial growth of Rhizoctonia solani or Fusarium oxysporum. Strains of Rhizobium leguminosarum (No.9), Azotobacter chroococcum (No.12) and Pseudomonas fluorescens (No. 6) recorded the highest inhibition zone against two tested pathogenic fungi and were used in the present study. Generally, under greenhouse and field conditions, all the tested PGPR strains significantly reduced root-rot and wilt incidence and increased the percentage of survived plants compared to control (infested soil). Combination among R. leguminosarum+ A. chroococcum + P. fluorescens was more effective in controlling root-rot and wilt diseases, increasing growth parameters, yield components, photosynthetic pigments, activities of nitrogenase, dehydrogenase and total phenols. Obtained results clarified the importance of PGPR in controlling pathogenic fungi, enhancing growth parameters of faba been plants compared to chemical fungicide and lowering chemical fertilizers application.

Tomato suffers from several diseases at all stages of its life. Blackmold, caused by Alternaria alternate (Fr.) Keissler is one of the most important postharvest disease of tomato. The effect of various concentrations of chitosan solution on A. alternata the causal agent of blackmold disease of tomato fruits on mycelial growth was studied. The isolate was tested in vitro using PDA amended with seven concentrations of chitosan (0, 1, 2, 3, 4, 5 and 6 mg ml -). Chitosan significantly (P < 0.05) inhibited the radial mycelial growth of this fungus by 67.4% at 6 mg ml 1 concentration. Tomato fruits treated with aqueous solution of chitosan compared with the Ipromise ® fungicide (Thiophonate-methyl 20% + Iprodione 20%) was artificially inoculated with A. alternata and incubated at 8, 18 and 28°C. Lesion diameters and total phenolic contents were recorded 7 and 14-days after inoculation. Chitosan also, significantly (P < 0.05) reduced the lesion diameters of tomato fruits which were smaller for all treatments when stored at 8°C compared to the control treatment. Chitosan treatment resulted in the highest increase in total phenolic contents over the untreated control. Whereas a less increase in total phenolic contents was recognized in fungicide treatment. In all treatments, total phenolic contents increased first and declined at the end of storage. The results of this study indicate that chitosan was a alternative safe coating method especially when stored at low temperature degree for prevents tomato fruits blackmold disease which causes economic losses during transportation, marketing and storage.

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